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Hey Jared, a completely valid question. It's always hard when a radiologist contradicts what your line thinking has always been.
The other members of the SIG group who contributed to this answer and myself broadly agree with you in the sense that raised velocities in the coeliac axis during full expiration can be associated with MALS.
One of our SIG members documents if there is significant PSV difference between inspiration and expiration in the Coeliac artery even if the PSV is slightly under 350cm/s, as getting the correct Doppler angle in the Coeliac axis can sometimes be difficult.
This is an extract from the Journal of medial ultrasound that backs that point up a bit that they suggested we steer your way. The study isn't the most recent but the principal still stands - Median Arcuate Ligament Syndrome 2003
''The median arcuate ligament is found at the T12-L1 level and bridges the crura of the diaphragm just anterior to the aorta. In patients with the median arcuate ligament syndrome, the celiac artery is compressed by the median arcuate ligament with expiration. With inspiration, the celiac artery descends in the abdominal cavity, resulting in a more vertical orientation of the celiac artery, which often relieves the compression. With the patient in the erect position, the celiac artery descends farther in the abdominal cavity, resulting in an even more vertical orientation of the celiac artery and relief of compression by the ligament''
Below is another extract from a much more recent publication which details some other nuances to be aware of that another member thought might be useful
Pellerito, John S., and Joseph F. Polak. Introduction to Vascular Ultrasonography. Seventh edition. Philadelphia, Pennsylvania: Elsevier, 2020. Print. Revxin Chapter 26 p 547-581
A potential pitfall for celiac artery stenosis is the median arcuate ligament (MAL) syndrome. The MAL is a fibrous band that extends from the diaphragmatic crura on either side of the aortic hiatus. The MAL usually passes just superior to the celiac artery. In some people, however, the MAL passes along the anterior margin of the celiac artery and may cause celiac artery compression during expiration. During the examination, the examiner may observe a characteristic change in the appearance of the celiac artery during different phases of the respiratory cycle. On expiration, the celiac artery assumes a hook-like appearance because of compression of the vessel by the ligament, and on inspiration, the artery takes a neutral, non-compressed course. With pulsed Doppler, mechanical compression of the celiac artery by the MAL is detected as increased PSV during expiration. On inspiration, a normal PSV is observed. Therefore inspiratory and expiratory velocity measurements should be obtained whenever MAL syndrome is suspected. Chronic compression of the celiac artery by the MAL may produce a fixed stenosis of the celiac artery with an elevated PSV that persists during inspiration.
This member (like myself) doesn't use a particular PSV but looks for the hook appearance in expiration, and a change in velocity. If a change with inspiration/expiration can't be produced you can also get them to stand which lower the mesentery and relieve the compression.
General consensus is that the radiologist has it backwards :)
Majority of credit for this answer goes to Dan Rae and Donna Oomens.
Hope this helps.
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Sorry it's taken a while to get back to you.
The answer is a bit multi-faceted. In regards to forearm fistulae you are completely right, retrograde radial artery flow beyond the anastomosis is perfectly normal in instances where the palmer arch is intact, and depending on where you read this retrograde distal radial flow can make up to 25% of the overall volume flow. Some papers even suggest that in some fistulas the retrograde flow alone is actually sufficient to provide effective dialysis.
Being that you mostly see upper arm AVFs you are likely exposed to a higher proportion of patients with distal ischemia due to a higher prevalence of this symptom in this variety of AVF. This is because brachial artery anastomoses tend to be larger which create lower vascular resistance, that pull more blood through the fistula and away from the hand, which is a problem that’s compounded by the fact that this is the only inflow artery to the forearm, as opposed to a RCAVF where only one of three arteries to the hand is affected.
We also need to discuss the differentiation between steal and steal syndrome. Most BCAVF will demonstrate physical steal whether that’s a bit of bi-directional flow in the brachial artery beyond the anastomosis or a retrograde radial/ulnar artery. This can be totally asymptomatic but becomes steal syndrome when symptoms of ischemia are present which is, like you say, a purely clinical diagnosis.
These symptoms can often be worse during HD which for sonographers obviously isn’t great because we can’t scan them during this period to see if there is any haemodynamic change. In answer to your actual question though - the only useful information we can provide via ultrasound is the status of the fistula (functional? Volume flow? Stenoses?),forearm arteries (all patent?) and the palmer arch (intact?).
Hope this helps
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Hi Lauren,
We had a good chat about your question in our SIG meeting last night. It's a great question and we aim to get back to you with a full answer with reference papers by the end of next week.
Thanks for posting and feel free to ask any other vascular related questions.
Matt
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Thank you for your question.
2023 Guidelines confirm that, " As a sole finding, sonographically detected polycystic ovaries are not sufficient to make the diagnosis of PCOS, although they may represent a mild form of ovarian hyperandrogenism and insulin resistance."
As per available guidelines and position papers, Combined Oral Contraceptives (CoCs) are recommended as the first-line treatment in adult women with PCOS in order to regulate menses and/or improve features of hyperandrogenism. Alternatives to COCs include cyclic progestin therapy, continuous progestin therapy (progestin-only pills), or a progestin-releasing intrauterine device(IUD).
As per the 2018 International Evidence- based Guidelines from Monash: https://www.monash.edu/medicine/sphpm/mchri/pcos/guideline: “Reliable assessment of biochemical hyperandrogenism is not possible in women on hormonal contraception, due to effects on sex hormone-binding globulin and altered gonadotrophin-dependent androgen production. Where assessment of biochemical hyperandrogenism is important in women on hormonal contraception, drug withdrawal is recommended for three months or longer before measurement, and contraception management with a non-hormonal alternative is needed during this time.”
In view of the available evidence, we can conclude that PCOS assessment cannot be performed when the patient is on any form of contraception.
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Thank you for your question.
This is the most current ASA guideline for intimate examinations: https://www.sonographers.org/publicassets/cf41bf67-4f90-ec11-9107-0050568796d8/UPDATE---PUB_0602_GUIDELINE-Intimate-examinations-Consent-and-Chaperones-Jan22.pdf
Additionally, ASUM do not list this as a contraindication either: https://www.asum.com.au/files/public/SoP/curver/Obs-Gynae/Gynaecological-GL-2020.pdf
Patients should be above 18 as a legal informed consent must be obtained. But there is no specific requirement to exclude those who are not sexually active.
As always, Sonographers should adhere to their department protocols.
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I am right handed scanner but have taught myself to scan left handed for cardiac scans and a variety of MSK scanning . Definitely possible with allowing time for adjustments . My experience as a physio suggests long term relief requires a good physio with progression of exercises to strengthen wrist extensors, this take 3-6 mths in the chronic cases so persistance needed. If pain is inhibiting exercises and scanning then cortisone injection can help in the short term and PRP injections (into the tear) may also help if early treatment not helping
Are you properly managed through WorkCover with, useful input from the treating doctor, physio etc, and workplace management, through a return-to-work coordinator.
Wages are covered by insurance while under WorkCover care so it is a good idea to have the sonographer at work helping with other tasks. (Are desk duties an option?)
Another possible option while in recovery mode is to be rostered as a trainer for students, supervising and overseeing their actions, without actually scanning. That way the injured sonographer remains engaged with the workplace, and maintains a sense of worth and value, and students get a real boost to their training. I have used this option in the past with very good results.
Hope this helps
Let us know if issues are ongoing
Peter Esselbach
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Thank you for your question.
Uterine length is measured from fundus to the external os of the cervix. Uterine width is the maximum transverse diameter. Uterine height is the maximum AP diameter.
Uterine volume will vary between nulliparous and parous states. A normal range would be approximately 100-150ml, again depending on patient history.
Attached is an article that may provide additional information.
http://www.ijmse.com/uploads/1/4/0/3/14032141/ijmse_2016_volume_3_issue_3_page_305-309.pdf
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Thank you for your question.
Ultrasound is often the first and usually the only imaging modality used to evaluate placental abruption, but an index of suspicion should be maintained for the diagnosis since ultrasound is relatively insensitive for the diagnosis. This is partly because a retroplacental hematoma may be identified only in 2-25% of all abruptions.
The echogenicity of hematomas depends upon their age. Acute hematomas imaged at the time of symptoms tend to be hyperechoic or isoechoic compared to the adjacent placenta. As the hematoma is commonly isoechoic to the placenta, it may be mistaken for focal thickening of the placenta.
Common locations are subchorionic (between the placenta and the membranes), retroplacental (between the placenta and the myometrium), and preplacental (between the placenta and the amniotic fluid). Retroplacental hematomas have a variable appearance; they can appear solid, complex, and hypo-, hyper-, or isoechoic compared with the placenta. If hypoechoic, then it is most probably resolving and therefore not acute. A retroplacental hematoma is more likely to be seen with more extensive placental separation and in patients who go on to have adverse maternal and perinatal outcome but its absence does not exclude the possibility of abruption, including a severe abruption, because blood may not collect and remain behind the placenta. Other findings suggestive of abruption include a subchorionic collection of fluid (even remote from the placental attachment site), echogenic debris in the amniotic fluid, or a thickened placenta; especially if it shimmers with maternal movement ("Jello" sign), placental thickening to over 5.5cm and separation of placental edges. However the main aspect to remember is that ultrasound may not always detect placental abruption so in an emergency it is best to manage based on clinical findings.
References for added info:
"Acute placental abruption: Pathophysiology, clinical features, diagnosis, and consequences" from Up To Date
TropI, Levine D. Hemorrhage during pregnancy: sonography and MR imaging. AJR Am J Roentgenol 2001; 176:607.
Shinde GR, Vaswani BP, Patange RP, et al. Diagnostic Performance of Ultrasonography for Detection of Abruption and Its Clinical Correlation and Maternal and Foetal Outcome. J Clin Diagn Res 2016; 10:QC04.
Qiu Y, Wu L, Xiao Y, Zhang X. Clinical analysis and classification of placental abruption. J Maternal Fetal Neonatal Med 2021; 34:2952
Yeo L, Ananth CV, Vintzileos AM. Placental abruption, Lippincott, Williams &Wilkins, Hagerstown, Maryland 2003.
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Thank you for your question. We've attached two articles that review cesarean section scar measurements in the third trimester for you. We found these quite informative.
https://obgyn.onlinelibrary.wiley.com/doi/10.1002/ijgo.13902https://obgyn.onlinelibrary.wiley.com/doi/full/10.1002/uog.15786
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Hello, thanks for your question. This SIG deals with paeds and adults, not foetal. I would suggest you redirect your question to the Woman's Health SIG.
Thanks
Anthony
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Thank you for your question.
We encourage you to check the reference of the charts on the ultrasound machine(s) in your department and source the original paper to find out how the BPD should be measured according to the charts being used.
Across Australia there is a large range of charts being used. Hadlock is quite common for EFW. Chitty is another chart often referenced.
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Thank you for your question.
An ASA guideline is currently being prepared on this topic.
Existing recommendations are to perform a transvaginal examination when requested for high risk patients or when transabdominal imaging demonstrates a shortened cervix.
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Hello Colleague,
In my department we follow the attached ASUM-ACIPC guidelines for infection control (attached).
If the patient's scrotal skin is intact, on scan completion we wipe the probe with a TB Oxivir wipe (as we do with all examinations) only.
We only high level disinfect the probe if the scrotal skin is broken, or the probe comes directly in contact with bodily fluids.
Hope this helps,
Marilyn Zelesco
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Thank you for your question.
This can be quite specific to patient condition post partum. Ie; stitches, caesarean section, etc. and may depend on patient consent or direction from the referrer.
However, typically 28 days post partum is considered acceptable for a transvaginal ultrasound.
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Hi Jackie,
Thank you for your suggestion. We will pass this along to the Education Advisory Committee.
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Thank you for your question.
Most growth scans are plotted on a generalized population chart, and in this instance the referring midwife or physician would need to plot fetal growth on a customized chart and proceed on patient follow up and care based on that.
Below is an example of what could be stated on the sonographer impression sheet:
Growth measurements in this report are plotted on population based growth charts. It is recommended that EFW be plotted on a customised chart (eg. GROW). If the EFW is below the 10th centile on the customised chart, please refer for urgent Doppler assessment.
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Thank you for your question.
Current recommendations are for the NT to be performed between 11-14 weeks (45-84mm), with 3.5mm and above considered abnormal. The nuchal fold measurement is to be performed at the routine anatomy scan from 18-22 weeks. Typically less than 6mm is considered normal at the anatomy scan.
Limited literature exists regarding the nuchal fold measurement between 14-18 weeks. A local Obstetrician may be able to provide guidance if they are requesting this.
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Thank you for our first ask an expert question! It's a good one.
For renal arteries (and any artery really for that matter) you ideally want to maintain a consistent Doppler angle as close to 60degrees as possible. It's my understanding that the flow velocities published in the literature are based on Doppler angles corrected to 60degrees. For grading proximal renal artery stenosis I prefer using renal-aortic-ratio (RAR) which is renal artery stenosis velocity divided by aortic velocity at renal level.
It can be hard with abdominal vascular scans to maintain an angle of 60 because you can't steer the beam so you need to heel and toe the probe to the best of your ability to create this angle. In the event you simply can't achieve an angle of 60, and don't I necessarily advocate for this, then angles of 45-60 have been shown to produce results with acceptable degrees of error. It goes without saying though that if you interrogate a renal artery stenosis with an angle of say, 48degrees then you must use the same angle in the aorta to produce a reliable RAR. General rule of thumb is that an RAR of >3.5 equates to a >60% stenosis.
For intra-renal arteries we don't correct Doppler angle (angle of 0degrees) at the lab I work at because we only measure resistive indices at the upper, mid and lower poles.
I'm sure the other vascular SIG members will be able to provide supplementary information - hope this helps!
Matt
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Hi Sally,
I am assuming this is for a foetal scan?
Ta
Anthony
Disclaimer: by using this service you recognise that the information provided is general in nature; it does not constitute professional advice. Any views expressed are those of individual(s) and may not reflect ASA’s views. The ASA does not endorse any product or service identified. You use any information provided at your sole risk and the ASA is not responsible for any errors or for any consequences arising from that use.
Hello Gayle
The cardaic SIG has had a hard think about your issues and drafted this reply to you. Please not, this is NOT legal advice not work related advice. This is a group of sonographers putting our collective thoughts down to support a fellow cardiac scanner.
Best wishes
Anthony Wald
SIG Cardiac chair
Response-Ask-SIG-Aug-2023.pdf